Ultrasonic endoscope probes are used to monitor internal regions of a patient, for example, organs such as the heart. An ultrasonic endoscope typically includes a shaft for insertion into body cavities of a patient such as the esophagus. At the tip of the shaft is a sensor head containing an array of ultrasonic sensor elements for monitoring internal organs. The sensor elements are electrically connected to an intermediate circuit housed in the sensor head by a short flexible circuit or a connector. A coaxial cable is electrically connected to the intermediate circuit and transmits electrical signals through the shaft between the sensor elements and the handle of the probe. The probe handle controls the operation of the endoscope.
The intermediate circuit or connector adds to the size of the sensor head. Some sensor heads having intermediate circuits, especially high density sensor heads with a large number of ultrasonic transducer elements, are too large for insertion into small body cavities such as a child's esophagus.
There is a continuing need for an ultrasonic sensor endoscope having a reduced size sensor head. Additionally, the diameter of the shaft must be small enough for insertion into small body cavities. Furthermore, the shaft should be flexible in all directions and also capable of being bent in a sharp radius in the region close to the sensor head in order to negotiate tight curves in body cavities. This allows the sensor head to be positioned for diagnostic utility. Further, even in non-endoscopic applications such as a transthoracic probe, cables are typically thick and somewhat cumbersome due to the lack of flexibility.